package com.hmdp.service.impl;

import com.hmdp.dto.Result;
import com.hmdp.entity.VoucherOrder;
import com.hmdp.mapper.VoucherOrderMapper;
import com.hmdp.service.ISeckillVoucherService;
import com.hmdp.service.IVoucherOrderService;
import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
import com.hmdp.utils.RedisIdWorker;
import com.hmdp.utils.UserHolder;
import org.redisson.api.RLock;
import org.redisson.api.RedissonClient;
import org.springframework.aop.framework.AopContext;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.core.io.ClassPathResource;
import org.springframework.data.redis.core.StringRedisTemplate;
import org.springframework.data.redis.core.script.DefaultRedisScript;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;

import javax.annotation.PostConstruct;
import java.util.Collections;
import java.util.concurrent.ArrayBlockingQueue;
import java.util.concurrent.BlockingQueue;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;

/**
 * <p>
 * 服务实现类
 * </p>
 *
 * @author 虎哥
 * @since 2021-12-22
 */
@Service
public class VoucherOrderServiceImpl extends ServiceImpl<VoucherOrderMapper, VoucherOrder> implements IVoucherOrderService {
    @Autowired
    private ISeckillVoucherService iSeckillVoucherService;
    @Autowired
    private RedisIdWorker redisIdWorker;
    @Autowired
    private StringRedisTemplate redisTemplate;
    @Autowired
    private RedissonClient redissonClient;
    private static final DefaultRedisScript<Long> SECKILL_SCRIPT;
    private BlockingQueue<VoucherOrder> orderTasks =new ArrayBlockingQueue<>(1024*1024);
    private static final ExecutorService SECKILL_ORDER_EXECUTOR = Executors.newSingleThreadExecutor();
    private IVoucherOrderService proxy;
    static {
        SECKILL_SCRIPT=new DefaultRedisScript<>();
        SECKILL_SCRIPT.setLocation(new ClassPathResource("seckill.lua"));
        SECKILL_SCRIPT.setResultType(Long.class);
    }

    @PostConstruct
    private void init(){
    SECKILL_ORDER_EXECUTOR.submit(new VoucherOederHanlder());
    }

    private class VoucherOederHanlder implements Runnable{

        @Override
        public void run() {
            while (true){
                //1.获取队列中的订单信息
                try {
                    VoucherOrder voucherOrder = orderTasks.take();
                    hanlderVoucherOrder(voucherOrder);
                } catch (Exception e) {
                    log.error("处理订单异常{}",e);
                }
            }
        }


    }

    private void hanlderVoucherOrder(VoucherOrder voucherOrder) {
        Long userId = voucherOrder.getUserId();
        RLock lock = redissonClient.getLock("lock:order:" + userId);
        boolean isLock = lock.tryLock();

        if (!isLock){
            //获取锁失败；返回错误信息或重试
            log.error("不允许重复下单");
            return;
        }
        //获取代理对象
        try {
//            proxy = (IVoucherOrderService) AopContext.currentProxy();
            proxy.createVoucherOeder(voucherOrder);
        } finally {
            lock.unlock();
        }
    }




    @Override
    public Result seckillVoucher(Long voucherId) {

        Long userId = UserHolder.getUser().getId();
        //1.执行lua脚本
        Long result = redisTemplate.execute(SECKILL_SCRIPT,
                Collections.emptyList(),
                voucherId.toString(), userId.toString());
        //2.判断结果是否为0
        int r=result.intValue();
        if (r!=0){
            return Result.fail(r==1?"库存不足":"不能重复下单");
        }
        //2.1不为0，代表没有购买资格

        //2.2为0，有购买资格，把下单信息保存到阻塞队列
        VoucherOrder voucherOrder = new VoucherOrder();
        long orderId = redisIdWorker.nextId("order");
        voucherOrder.setId(orderId);
        voucherOrder.setUserId(userId);
        voucherOrder.setVoucherId(voucherId);
//TODO 保存阻塞队列
orderTasks.add(voucherOrder);
proxy= (IVoucherOrderService) AopContext.currentProxy();
        //3.返回订单id
        return Result.ok(orderId);
    }

    @Transactional
    public void createVoucherOeder(VoucherOrder voucherOrder) {
        Long userId = voucherOrder.getUserId();
        int count = query().eq("user_id", userId).eq("voucher_id", voucherOrder).count();
        if (count > 0) {
            log.error("用户已经购买过一次了");
        }

        boolean success = iSeckillVoucherService.update().setSql("stock = stock - 1")
                .eq("voucher_id", voucherOrder.getVoucherId())
                .gt("stock", 0)
                .update();

        if (!success) {
//            throw new RuntimeException("库存不足");
            log.error("库存不足");
        }


        save(voucherOrder);
    }



    /*@Override
//    @Transactional
    public Result seckillVoucher(Long voucherId) {

        SeckillVoucher voucher = iSeckillVoucherService.getById(voucherId);
        if (voucher.getBeginTime().isAfter(LocalDateTime.now())) {
            return Result.fail("秒杀尚未开始");
        }
        if (voucher.getEndTime().isBefore(LocalDateTime.now())) {
            return Result.fail("秒杀已经结束");
        }
        if (voucher.getStock() < 1) {
            return Result.fail("库存不足");
        }
        Long userId = UserHolder.getUser().getId();
//        SimpleRedisLock lock = new SimpleRedisLock("order:" + userId, redisTemplate);
        RLock lock = redissonClient.getLock("lock:order:" + userId);
        boolean isLock = lock.tryLock();

        if (!isLock){
            //获取锁失败；返回错误信息或重试
            return Result.fail("不允许重复下单");
        }
        //获取代理对象
        try {
            IVoucherOrderService proxy = (IVoucherOrderService) AopContext.currentProxy();
            return proxy.createVoucherOeder(voucherId);
        } finally {
            lock.unlock();
        }


    }*/



}
